The present invention is directed to an improved barrel construction for a muzzle loading firearm and a method of forming the barrel.
Most modern muzzle loading firearms are provided with rifling along the inner cylindrical surface which defines the bore of the barrel. The rifling improves shooting accuracy, particularly when the firearm is utilized with bullet shaped projectiles. The rifling consists of a plurality of spaced grooves which extend helically along the length of the barrel. The areas between the grooves are defined as lands. The lands also extend helically along the length of the barrel. In order for the rifling to be effective in imparting spin to the projectile, the outer diameter of the projectile is slightly larger that the inner diameter of the lands of the inner surface of the barrel and slightly smaller than the inner diameter of the grooves of the inner surface of the barrel.
When the projectile is inserted into the bore of the barrel, the lands of the rifling impress into the projectile. Therefore, considerable force is required to advance the projectile along the bore. The projectile is caused to rotate about its longitudinal axis as it is advanced along the bore from the muzzle. This makes the projectile loading step quite difficult, particularly at the muzzle end of the barrel. A traditional ramrod is too awkward to be used for the initial projectile inserting step (starting). A short ramrod known as a "short starter" is used to force the projectile into the barrel for a short distance. A traditional ramrod is then used to push the projectile to its final firing position. A special starting tool can also used to introduce the projectile into the muzzle of the firearm. The starting tool includes a body which has a socket for receiving the projectile, nose first. A handle is connected to the body by an auger. The auger is threaded into the body to the socket for engaging the projectile. The base of the projectile extends beyond the socket and is axially aligned with the muzzle of the firearm. The handle of the started is pushed toward the muzzle. This causes the auger to push the projectile out of the socket and into the muzzle. Because of the difficulty of "starting" the projectile, it is difficult to control the axial alignment of the projectile within the bore regardless of what type of tool is used. A slight axial misalignment of the projectile within the bore has a negative effect on the shooting accuracy of the firearm. The step of forcing the projectile into the muzzle also causes excessive wear and damage to the muzzle end of the barrel. Additional wear to the rifling at the muzzle end of the barrel also occurs as a result of cleaning operations.
Attempts have been made by some shooters to overcome the problems associated with the use of rifling enhanced muzzle loading firearms. One such attempt comprises cutting off a short portion of the end of the barrel and enlarging the bore of the cut-off portion of the barrel. Prior to removal of the end portion of the barrel, small holes are drilled in the barrel. The holes are parallel to the longitudinal axis of the barrel. The holes extend beyond the portion of the barrel which is be cut-off. This enables locating pins to be inserted into the holes to enable the cut-off portion of the barrel to be temporarily reunited with the main portion of the barrel. This insures that the cut-off portion of the barrel will be returned to its original position so that the bore of the cut-off portion of the barrel is aligned with the bore of the main portion of the barrel. The cut-off portion of the barrel receives the projectile quite freely and enables the projectile to be loaded more easily into the main portion of the barrel. The short portion of the barrel is then removed prior to firing of the firearm. This solution to the problem of projectile loading has not been widely employed. Very few sportsmen have the means or the skills required for such a procedure. Although the cut-off barrel portion can be returned to its original position on the barrel, there is no guarantee that the axis of the enlarged bore of the cut-off barrel portion will be concentric with the axis of the bore of the main portion of the barrel. The application and removal of the cut-off portion of the barrel adds two extra steps in the loading sequence. The length of the barrel is effectively shortened which has a negative effect on the balance and shooting accuracy of the firearm. Some muzzle loading rifles are sold with a "false muzzle". A "false muzzle" is a device produced by making the barrel several inches longer than intended for shooting during its manufacture. After providing rifling in the bore of the barrel the end of the barrel is cut-off. The cut-off portion of the barrel is then referred to as the "false muzzle". The "false muzzle" is then provided with locating pins which fit into corresponding holes in the muzzle end of the barrel to insure alignment of the rifling between the barrel proper and the "false muzzle". The initial loading of the projectile occurs in the "false muzzle" apart from the firearm. The "false muzzle" is then attached to the muzzle end of the firearm to complete the projectile loading process. Since the "false muzzle" takes the majority of the wear in the loading and cleaning processes, the life of the firearm is lengthened and its accuracy is preserved. However, the initial starting step for the projectile is still difficult even with the "false muzzle" and the problem of misalignment of the projectile relative to the bore of the barrel is not eliminated. Also, since the "false muzzle" is a functional part of the original firearm, the value of the firearm is significantly diminished if the "false muzzle" is lost. The "false muzzle" cannot be replaced since it was an integral part of the barrel during the bore drilling and rifling processes. A variation of the "false muzzle" concept includes a device which is made as described above and which the bore of the "false muzzle" from the loading face of the "false muzzle". This enables the projectile to be inserted into the bore of the "false muzzle" by finger pressure. All false muzzles must be removed from the barrel before firing of the firearm and reapplied before reloading of the firearm. These two extra steps greatly increase the time required for each loading and firing operation. These and other difficulties experienced with the prior art rifled barrels for muzzle loading firearms have been obviated by the present invention.
It is, therefore, a principle object of the invention to provide a rifled barrel for a muzzle loading firearm which greatly facilitates the step of loading of the projectile into the bore of the barrel.
Another object of the invention is the provision of a rifled barrel for a muzzle loading firearm which provides for more accurate centering of the projectile in the barrel, thereby resulting in greater firing accuracy for the firearm.
A further object of the present invention is the provision of a rifled barrel for a muzzle loading firearm which does not require the need for a short starter to initiate the loading step of a projectile into the bore of the barrel.
It is another object of the present invention to provide a method of forming a barrel for muzzle loading firearm which results in a barrel that is easier to projectile load and does not require a short starter to initiate projectile loading of the projectile, and which improves the accuracy of the firearm by providing for more accurate axial alignment of the projectile within the bore of the barrel.
A still further object of the invention is the provision of a method of forming a rifled barrel for a muzzle loading firearm and the barrel which is produced thereby for enabling a projectile to be loaded process easily, quickly, and more accurately so that overall loading takes substantially less time and shooting accuracy is significantly improved.
It is a further object of the invention to provide a counterboring tool for enlarging the bore at the muzzle end of a muzzle loading firearm.
With these and other objects in view, as will be apparent to those skilled in the art, invention resides in the combination of parts set forth in the specification and covered by the claims appended hereto.